Answer:
C
Step-by-step explanation:
To begin, since a and b are parallel and are going through the same line, we can say that angles 1,2,3,4 are equal to 5,6,7,8 respectively. Next, since 2 and 3 are opposite angles (angles 2 and 4 add to 180, and so do 3 and 4, so 2=3), angle2=angle3. Next, since angle 3 is equivalent to angle 7, ∠7=68° (C)
